Opiate dependence (OD) and Borderline Personality Disorder (BPD), separately and together, are significant public health problems. Comorbidity between OD and BPD significantly compromises treatment outcome. Treatment-resistant opiate use places a significant burden on individuals and their families, as well as public health and criminal justice systems. An ongoing multisite clinical trial at the University of Washington and Duke University Medical Center is examining the effectiveness of behavioral treatments (DBT or I/GDC) plus suboxone (an opiate drug replacement) in treating this challenging population. BPD is associated with difficulties in emotion regulation, which is thought to contribute to treatment resistance in substance dependence. Brain imaging studies in BPD individuals indicate differential activation in prefrontal-cingulate cortices and their interactions with limbic regions, and studies of emotion regulation in healthy adults have revealed activity in similar networks. Likewise, a similar network is implicated in drug cue responsivity in substance abusers. As an extension of the treatment study, the present supplemental application proposes to examine neurobiological mechanisms of treatment success. Functional magnetic resonance imaging (fMRI) will be used to examine activation of this network in response to both drug-related images as well as to strongly valenced images. The "oddball" task used in the proposed study has been demonstrated to activate dorsal cognitive-attention systems, ventral emotional-motivational systems, and executive regions that interface between these two systems. A subsample of participants in the ongoing treatment study at each site will undergo a series of fMRI scans over the course of the one-year treatment using the oddball task. A nonclinical control group will be scanned at comparable time intervals to control for time-based changes in responsivity. HLM-based techniques will be used to analyze changes in activation over time, as well as the relationship between activation changes and treatment outcome (i.e., post-treatment drug use, suicidality, and coping skills). Given its focus on increased emotion regulation skills, it is hypothesized that changes in activation in response to both drug cues and emotional stimuli will mediate treatment success in participants receiving DBT. The proposed study will collect pilot data and feasibility information in preparation for a future large-scale study. [unreadable] [unreadable] [unreadable] [unreadable]